The invention herein described concerns a process for selective post-emergence weeding and the new products by which the process can be implemented.
There are two differing techniques by which the weeding of crops can be effected. The one consists of pre-emergence dissemination of the herbicide, by which is meant its dissemination before the appearance of said crops above the ground, and usually before the emergence of the undesirable vegetation. The other consists of post-emergence dissemination of the herbicide, by which is meant its dissemination after the germination of said crops and their appearance above the ground, and usually after the appearance of the undesirable vegetation. Obviously the action of the herbicide is quite different in the two cases, and it is self-evident that in most cases it will be necessary to use differing herbicides for the two differing situations. Furthermore, post-emergence weeding calls for a special selection of the herbicide, the choice depending on the crop to be treated and also on the undesirable vegetation to be destroyed. Finally, the stage of development of the crop that is suitable for weeding by means of a given herbicide can have considerable bearing on the results of such treatment.
Consequently, the suitable implementation of post-emergence weeding will require the use of herbicides that are especially active against the undesirable vegetation and are absolutely harmless to the crops being treated.
The invention herein described has for its object the furnishing of means whereby the post-emergence weeding of crops can be carried out. It concerns both a process for carrying out the weeding and certain products used to implement this process.
It has already been established:
1. That certain herbicides possess little effectiveness for use in post-emergence weeding;
2. That certain other herbicides which are ineffective or useless for post-emergence weeding can be effectively used for the post-emergence weeding of crops by the addition to these herbicides of a certain quantity of non-phytotoxic oil.